LAMMPS (17 Apr 2024 - Development - patch_5May2020-18508-g3c0eaf6870-modified)
# ------ 2D Taylor Green vortex ------ #

dimension          2
units              lj
atom_style         rheo
boundary           p p p
comm_modify        vel yes
newton off

# ------ Create simulation box ------ #

variable           n equal 1.0
variable           cut equal 3.0

region             box block 0 40 0 40 -0.01 0.01
create_box         1 box
Created orthogonal box = (0 0 -0.01) to (40 40 0.01)
  2 by 2 by 1 MPI processor grid
lattice            sq ${n}
lattice            sq 1
Lattice spacing in x,y,z = 1 1 1

create_atoms       1 region box
Created 1600 atoms
  using lattice units in orthogonal box = (0 0 -0.01) to (40 40 0.01)
  create_atoms CPU = 0.001 seconds

displace_atoms     all random 0.1 0.1 0 135414 units box
Displacing atoms ...

# ------ Model parameters ------ #

variable           rho0 equal 1.0
variable           mp equal ${rho0}/${n}
variable           mp equal 1/${n}
variable           mp equal 1/1
variable           cs equal 1.0
variable           eta equal 0.05
variable           zeta equal 1
variable           dt_max equal 0.1*${cut}/${cs}/3
variable           dt_max equal 0.1*3/${cs}/3
variable           dt_max equal 0.1*3/1/3
variable           Dr equal 0.1*${cut}*${cs}
variable           Dr equal 0.1*3*${cs}
variable           Dr equal 0.1*3*1

mass               * ${mp}
mass               * 1
set                group all rheo/rho ${rho0}
set                group all rheo/rho 1
Setting atom values ...
  1600 settings made for rheo/rho
set                group all rheo/status 0
Setting atom values ...
  1600 settings made for rheo/status

variable           u0 equal 0.05
variable           uy atom  ${u0}*sin(2*PI*x/lx)*cos(2*PI*y/ly)
variable           uy atom  0.05*sin(2*PI*x/lx)*cos(2*PI*y/ly)
variable           ux atom -${u0}*sin(2*PI*y/ly)*cos(2*PI*x/ly)
variable           ux atom -0.05*sin(2*PI*y/ly)*cos(2*PI*x/ly)
variable           d0 atom ${rho0}-${u0}*${u0}*${rho0}*0.25*(cos(4*PI*x/lx)+cos(4*PI*y/ly))/${cs}/${cs}
variable           d0 atom 1-${u0}*${u0}*${rho0}*0.25*(cos(4*PI*x/lx)+cos(4*PI*y/ly))/${cs}/${cs}
variable           d0 atom 1-0.05*${u0}*${rho0}*0.25*(cos(4*PI*x/lx)+cos(4*PI*y/ly))/${cs}/${cs}
variable           d0 atom 1-0.05*0.05*${rho0}*0.25*(cos(4*PI*x/lx)+cos(4*PI*y/ly))/${cs}/${cs}
variable           d0 atom 1-0.05*0.05*1*0.25*(cos(4*PI*x/lx)+cos(4*PI*y/ly))/${cs}/${cs}
variable           d0 atom 1-0.05*0.05*1*0.25*(cos(4*PI*x/lx)+cos(4*PI*y/ly))/1/${cs}
variable           d0 atom 1-0.05*0.05*1*0.25*(cos(4*PI*x/lx)+cos(4*PI*y/ly))/1/1

velocity           all set v_ux v_uy 0.0 units box

timestep           ${dt_max}
timestep           0.1

pair_style         rheo ${cut} artificial/visc ${zeta} rho/damp ${Dr}
pair_style         rheo 3 artificial/visc ${zeta} rho/damp ${Dr}
pair_style         rheo 3 artificial/visc 1 rho/damp ${Dr}
pair_style         rheo 3 artificial/visc 1 rho/damp 0.3
pair_coeff         * *

# ------ Fixes & computes ------ #

fix                1 all rheo ${cut} RK1 8 shift
fix                1 all rheo 3 RK1 8 shift
fix                2 all rheo/viscosity * constant ${eta}
fix                2 all rheo/viscosity * constant 0.05
fix                3 all rheo/pressure * linear
fix                4 all enforce2d

compute            rho all rheo/property/atom rho

# ------ Output & Run ------ #

thermo             200
thermo_style       custom step time ke press

dump               1 all custom 200 atomDump id type x y vx vy fx fy c_rho

run 10000

CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE

Your simulation uses code contributions which should be cited:

- @article{PalermoInPrep,
 journal = {in prep},
 title = {RHEO: A Hybrid Mesh-Free Model Framework for Dynamic Multi-Phase Flows},
 year = {2024},
 author = {Eric T. Palermo and Ki T. Wolf and Joel T. Clemmer and Thomas C. O'Connor},
}

CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE-CITE

Generated 0 of 0 mixed pair_coeff terms from geometric mixing rule
Neighbor list info ...
  update: every = 1 steps, delay = 0 steps, check = yes
  max neighbors/atom: 2000, page size: 100000
  master list distance cutoff = 3.3
  ghost atom cutoff = 3.3
  binsize = 1.65, bins = 25 25 1
  4 neighbor lists, perpetual/occasional/extra = 4 0 0
  (1) pair rheo, perpetual, half/full from (2)
      attributes: half, newton off
      pair build: halffull/newtoff
      stencil: none
      bin: none
  (2) compute RHEO/KERNEL, perpetual
      attributes: full, newton off
      pair build: full/bin/atomonly
      stencil: full/bin/2d
      bin: standard
  (3) compute RHEO/GRAD, perpetual, copy from (1)
      attributes: half, newton off
      pair build: copy
      stencil: none
      bin: none
  (4) compute RHEO/VSHIFT, perpetual, copy from (1)
      attributes: half, newton off
      pair build: copy
      stencil: none
      bin: none
Per MPI rank memory allocation (min/avg/max) = 6.835 | 6.835 | 6.835 Mbytes
   Step          Time          KinEng         Press     
         0   0              0.00062497276  0.00062607301
       200   20             0.00056200647  0.00056633785
       400   40             0.00050570968  0.00051098771
       600   60             0.00045586684  0.00046081672
       800   80             0.00041124523  0.00041549607
      1000   100            0.00037065341  0.00037412741
      1200   120            0.00033391585  0.00033580899
      1400   140            0.00030078316  0.00030057307
      1600   160            0.00027093231  0.00026842603
      1800   180            0.00024403239  0.00023839026
      2000   200            0.0002197865   0.00021148941
      2200   220            0.0001979269   0.00018659386
      2400   240            0.00017822267  0.00016430442
      2600   260            0.00016047141  0.00014408514
      2800   280            0.00014448504  0.00012574125
      3000   300            0.00013009159  0.00010869938
      3200   320            0.00011713578  9.414951e-05 
      3400   340            0.00010547564  8.1900579e-05
      3600   360            9.4982139e-05  7.1285649e-05
      3800   380            8.5538983e-05  6.1571123e-05
      4000   400            7.7040171e-05  5.3462572e-05
      4200   420            6.9390317e-05  4.6338308e-05
      4400   440            6.2503763e-05  3.9697323e-05
      4600   460            5.6303766e-05  3.4234465e-05
      4800   480            5.0721595e-05  3.0841338e-05
      5000   500            4.5695301e-05  2.7788566e-05
      5200   520            4.1169161e-05  2.5744409e-05
      5400   540            3.7093059e-05  2.3912739e-05
      5600   560            3.3421819e-05  2.2494185e-05
      5800   580            3.0114735e-05  2.1594384e-05
      6000   600            2.7135224e-05  2.1164421e-05
      6200   620            2.4450446e-05  2.0979349e-05
      6400   640            2.2030925e-05  2.0858567e-05
      6600   660            1.9850196e-05  2.098115e-05 
      6800   680            1.7884553e-05  2.1134827e-05
      7000   700            1.6112763e-05  2.1242242e-05
      7200   720            1.4515783e-05  2.1312763e-05
      7400   740            1.3076456e-05  2.1370947e-05
      7600   760            1.1779327e-05  2.1332126e-05
      7800   780            1.0610469e-05  2.1156562e-05
      8000   800            9.5573298e-06  2.0898126e-05
      8200   820            8.6085799e-06  2.0517958e-05
      8400   840            7.7539888e-06  1.9841551e-05
      8600   860            6.9843033e-06  1.9114769e-05
      8800   880            6.2911575e-06  1.8362959e-05
      9000   900            5.6669785e-06  1.7473404e-05
      9200   920            5.1049208e-06  1.6452745e-05
      9400   940            4.5987908e-06  1.5578629e-05
      9600   960            4.1429972e-06  1.4427274e-05
      9800   980            3.7324962e-06  1.3169649e-05
     10000   1000           3.3627455e-06  1.1938723e-05
Loop time of 38.2006 on 4 procs for 10000 steps with 1600 atoms

Performance: 2261743.875 tau/day, 261.776 timesteps/s, 418.841 katom-step/s
99.7% CPU use with 4 MPI tasks x no OpenMP threads

MPI task timing breakdown:
Section |  min time  |  avg time  |  max time  |%varavg| %total
---------------------------------------------------------------
Pair    | 8.2958     | 8.7273     | 9.3582     |  15.2 | 22.85
Neigh   | 0.034282   | 0.035689   | 0.037115   |   0.7 |  0.09
Comm    | 0.16788    | 0.17018    | 0.17278    |   0.4 |  0.45
Output  | 0.066977   | 0.06882    | 0.071704   |   0.7 |  0.18
Modify  | 28.483     | 28.793     | 28.962     |   3.6 | 75.37
Other   |            | 0.4053     |            |       |  1.06

Nlocal:            400 ave         402 max         399 min
Histogram: 2 0 0 1 0 0 0 0 0 1
Nghost:         307.25 ave         308 max         305 min
Histogram: 1 0 0 0 0 0 0 0 0 3
Neighs:        7618.25 ave        7697 max        7564 min
Histogram: 1 0 1 1 0 0 0 0 0 1
FullNghs:        13343 ave       13497 max       13258 min
Histogram: 1 1 1 0 0 0 0 0 0 1

Total # of neighbors = 53372
Ave neighs/atom = 33.3575
Neighbor list builds = 123
Dangerous builds = 0
Total wall time: 0:00:38
